Safety mechanism for uncoupling a shaft from the driving member of a machine



Oct. 27, 1953 A. VAN HAANDEL 2,656,906

SAFETY MECHANISM FOR UNCOUPLING A SHAFT FROM THE DRIVING MEMBER OF A MACHINE Filed March 13, 1951 2 Sheets-Sheet l Oct. 27, 1953 A. VAN HAANDEL SAFETY MECHANISM FOR UNC FROM THE DRI Filed March 13, 1951 2,656,906 OUPLING A SHAFT vmc MEMBER OF A MACHINE.

2 Sheets-Sheet 2 Patented Oct. 27, 1953 2,656,906 SAFETY MECHANISM FOR UNCOUPLING A SHAFT FROM THE D A MACHINE RIVING MEMBER OF Adrianus van Haandel, deceased, late of Helmond, Netherlands, by Johannes Hubertus van Haan- Helmond, Nether- Application March 13, 1951, Serial N 0. 215,399 In the Netherlands March 16, 1950 8 Claims.

This invention relates to improvements in safety mechanisms or devices of the type employed for uncoupling or declutching a driven shaft from the driving member of a machine, such as a crank-shaft or an eccentric type press.

More particularly, the invention relates to such a machine including a coupling member or sliding key extending parallel to the axis of the shaft into engagement with the driving member, the coupling member being maintained in coupled position by a spring and being moved out of coupling position by the action of a wedge-shaped member movable into the path of the key when the machine is in operation.

The primary object of the present invention is to provide a safety mechanism which will be operable automatically upon the occurrence of a default in the machine.

A further object of the invention is to provide a safety mechanism for machines of the type referred to which will be operable automatically with a minimum of movement and power on the occurrence of a default, such as a stoppage in the supply of material to the machine.

In accordance with the invention, the improvements are applied to safety mechanisms of the type referred to and include means operable on rotation of the shaft for rocking the wedgeshaped member into and out of the path of the coupling member or key without normally causing the wedge-shaped member to engage the coupling member or key, and means responsive to the occurrence of a fault in the operation of the machine for retaining the wedge-shaped member in its rocked position in the path of the coupling member or key, whereby the wedge-shaped member engages the coupling member or key and the latter is moved out of its coupling position with respect to the driving member.

In a preferred construction, the safety mechanism includes a cam carried by the shaft for rocking the wedge-shaped member to its uncoupling position, and a tongue, or stop, movable into a position to hold the wedge-shaped member in its uncoupling position. i

In this construction the tongue or stop is operated in response to some default in the operation of the machine so that it is moved into the path of the Wedge-shaped member to hold it in its uncoupling position. Very little power is, therefore, required for effecting the uncoupling of the shaft from. the driving member since the wedgeshaped member is periodically rocked into uncoupling position by the cam carried by the shaft.

The invention includes other features as described in the following detailed description of illustrative embodiments of the invention, as shown in the accompanying drawings forming a part of this application.

In the drawings:

Fig. 1 is a broken part of a machine including a shaft coupled to a driving member, the construction being of the type to which the safety mechanism of the present invention is applied;

Fig. 2 is a front elevational view, partly in sectuated position;

Fig. 3 is a view similar to that of Fig. 1, showgang the shaft uncoupled from the driving mem- Fig. 4 is a view similar to that of Fig. 2 taken on the line IV-IV of Fig. 3, showing the safety mechanism in actuated position;

Fig. 5 is a broken plan view of a part of the mechanism shown in Figs. 2 and 4;

Fig. 6 is a sectional view taken on the line VI-VI of Fig. 5; and

Fig. 7 is a front elevational view similar to that of Fig. 4, showing a modified form of construction including a braking means.

In Figs. 1 to 4 of the drawings, the machine therein shown comprises a shaft I which may be a crank-shaft or a shaft for driving an eccenpling of the wheel 4 to the shaft I.

The means for uncoupling the shaft and fly wheel, that is, the means for shifting the key 5 against the action of the spring 6, comprises a on the frame of the machine by a pin or shaft 9, this shaft 9 being parallel to the axis of the shaft I. The lever 8 includes an arm l0 extending under the shaft I the end of which is biased toward the shaft by a compression spring H supported at'a fixed point in the frame of the machine. The lever 8 also includes an arm l2 extending generally at right angles to the arm I!) and which is arranged to engage in a slot in the slidable key 5.

3 In accordance with the present invention, a roller I3 is mounted gon the arm I in a position to engage the peripheral surface of a cam I4, comprising a disc-like member having a cam surface mounted in spaced relation to the sleevel; and keyed to the shaft I by the. key}, Thecam member I4, including the disc-like membenmay be made as an integral part of the sleeve 2 and have essentially the hub and other structure shown in Figs. 1 to 4 of the drawings.

The shape of the cam l4 isshown in-Figsi 2 and 4 of the drawings and is suc'h that the. arms I0 and I2 are rocked at eachreyolution of the;

shaft I so that the upper end of the arm I2 is moved toward the shaft and then under normal conditions released so that it is -rocked away from the shaft in time to miss the pin 5-in=its rotation about the axis of the shaft I.

The upper end of the arm I2 is provided with a wes ae heh d mi rtion.- av n n. clinedsurface I'E; which is arranged to engage ahdwhieh tsen. elinedg ur ee I1 of t e s ot in the outer surface of -'th' e.key,5, asshown in Fig. 1 of the drawings. If the armIZ is held at t h hermestresit eh ith espect to hesh f I ewhieh itis me dl m h w e r r of t am J 4.. the s r jaee. 1 n es h fae ic hit; i het e .5 to. t eri hh to th position-sh wn in Fig. 3. This action talges place againstthe ia in qltee. f. th xihgfi; h i ha t :1 is uncoupled from thedri 4 e wheel 14:

. herderteef eet the hee e r i eelut in operation according to the inventi. ,1, v a means is rey q s h ch i snehsire qth c u r f h emede hl t in i eret eh. he ae ne for retaining the arm I2 'n its uncoupling posi-z eh.-.. h mechanismmpris a de. l8 ei htedeh. the rame them ad a en to the cam I4 and servingto g uide atongue or ,stop I9 int thera hei as aeer his. m un n the back of the arm, I2; This arrangement is shown hI ea 2,, ,4, hand hete sii e stop.v I 9 i reciprocated by a lever haying apin .y34ien easing e ehate .sletinthe pide B- hd in a ertieal, s ot. he vs p. he lev fl ;h n fixed to a shaft 2I car ried in bearings 35.; The hhesi e nd ithesha 2! rom t rn...2fl a i sieh. emig hieh i at ached o n i ui ehneeted-hhteohepr anumhe ef parts -Q hemeQ ine QI hefllhtifll nth e t h eei rrenee p au e i lti eh.. s, a l n d w hhe upplye ma e ieler t et ia s ppa e i ma e i irplrto themaehih the heret eh f. hel aiet e n sm hgi nin Fisso helb li tahk lev B is e h eu ly t ee s dhy the. ie. th she tt i otat v h ha ault o ur th hsuei o t is slipped into. h path. efthee mJ Z veeme pri in heiedeez hane hu n member s hat i i ...b o,eke i from movingiawa from e shaft I'. The key. .5,;.therefore, movesinto en easeme t. with he J esshai l o s t tter ert ene t ek ylas v.s ehi l a 3i eee:

ga shehld her. abutment 2 hthe rm. zs pinat e v e at hn i.t e shait n. tart hs ,t mach heeiter t e ult. h s been rr t d. h shaft 2 I must be rotated in reverse to, a ,small tent; emithe ste I9 etra t d in. e h r to permitthe. sprin I l to pi he e er flftherebypere mi tingthekey fitoengaee hthe o 1 Of t ri'v i h el t e ti he. .b afn aeti h hhh .6--

In order to aid in stopping the rotation of, the shaft I when itlis tobe uncoupled bythe safety mechanism described above, the braking arrangeence characters plus the letter a.

'1 the apparatus includes a braking disc or drum 2;3: k eyed to the shaft I and a brake band 24 extending, around the disc and attached at one end 29 to the arm I0 of the rocking lever 8. Thelperiphery. of .the. coupling sleeve 2 may be employed as the-braking disc. The shaft I carries' a-cam--25 -used for actuating the brake band 2A,;this,cam beingengaged by a roller 21 mounted on arm.2figof a beltecrank lever pivoted on a pin or shaft 32; and having a second arm 28 extending laterally land'abiased by a compression spring 33. The-spring :rocks the arm 26 to maintain engagementpf the roller 21 with the cam 25. The opposite end 30 of the brake band 24 is attached to the end of the arm 28 by means of an adjustable connection 31: Thecarn' 25'-may be mounted adjacentthe -cam- I40,- and onthesame-mounting:-

Since-the brake'band 24-is attached to the arm Iila, it is pulledsomewhat at every-movement of "the arm IZa-inthe-direction ofthe shaft Ia, but at that time the-roller-21'is not in contact with the 'cam 25: The position ofthe cam 25 is selected sothat-under normal conditions it effects pulling of the brake band 24 when-the-roller I3a/is'in the low part of the cam 14a andthe-arm-Hdwis' free from engagement -by-th'e key-Eamnwhenthe end I 5a has passed thecouphng member--55 However; when the tongue IBa-blocks the movement of the arm I2a-and retainsit in theuneoupling position; the pull onthe brake band 24 by the arm-Illa is retained, and as the key dais being-moved-to its uncoupled position,- the cam 25 engages the roller 21 to-further tighten upon the brake band 24- 50mm theshaft I is-braked effectively during the-actionof-the uncoupling mechan-ism;- thereby stopping the-shaft l=less abruptly and--causing the application of less pressure-'on -the' shoulder orabutment- 22a of the uncoupling arm 12a.-

Thesafety mechanism has the-advantage that the uncoupling arm I2 is-constantly-moved 'into a position to effect the uncoupling of the fly wheel and ;the stopping of the shaft I at any instant upon the happening of a fault in the-operation of the machine. Such an uncoupling,*howeven-does not -become effeetive, andthe-arm- I2-is always moved -'out of its uncoupling position, unless-the arm-is blocked by the tongue or stop I 9;

Various 1 knowntypes of means maybe employedfor operatingthe-shaft 2I fromvarious parts of the machineinresponse to the occurrenceof a faultyoperation-so-as to effect stopping of the machine. such 'means arewell 'known'in the art and need-not bedescribed in-conne-ction with the actual safety mechanismclaimed in-the present application: Furthermore, such means W111 eifectively move the tongue I9 with the use of verylittle -power.;;

What is claimed as new is 1.

1.111, a safety mechanism'for disengaging. a coupling betweena shaft and the driving member ofja machine including a coupling member slidable parallel to the shaft, means for .biasing.the coupling. member to coupling. position and (a wedge-shaped member movable into'the path of the .couplingmember for engaging and moving it out j of its I coupling position, the improvement comprising means for biasing said.wedge-shaped member away .from the. path Offth'e coupling member, means operable on rotation of the shaft for rocking said wedge-shaped member into the path of said coupling member without normally causing said wedge-shaped member to engage said coupling member, means responsive to the occurrence of a fault in the operation of the machine for retaining the wedge-shaped member in its rocked position in the path of said coupling member, whereby the wedge-shaped member is engaged by the coupling member and the latter moved out of coupling position, a braking means operable on the shaft and interconnected with said wedge-shaped member, and means operable for applying said braking means when the wedgeshaped member is retained in its uncoupling position and engaged by the coupling member.

2. In a machine including a shaft to be driven, a driving member for the shaft, a slidable key carried by the shaft for coupling the shaft to the driving member, means biasing the key to its coupling position, and a safety mechanism including a pivoted arm to be engaged by the key for sliding it out of engagement with the driving member, the improvement comprising a cam, carried by the shaft, for rocking said arm into its uncoupling position at a point in advance of that at which it would be engaged by said key, means for biasing said arm away from its uncoupling position, and a stop means operable in response to the occurrence of a fault in the operation of the machine for retaining said arm in its uncoupling position when moved thereto by said cam, whereby said arm is engaged by said key and the key shifted out of engagement with the driving member.

3. A machine as claimed in claim 2, including a brake disc attached to the shaft, a brakeband engaging the periphery of said disc and having one end interconnected with said pivoted arm and pulled thereby when said arm is rocked to its uncoupling position, and means operatively as sociated with the shaft and operated by rotation prises one arm of a pivoted bell-crank lever, the i said one end of the brake band being connected to the other arm of the pivoted bell-crank lever.

6. A machine as claimed in claim 2, including means for stopping rotation of the shaft when the slidable key is in engagement with the pivoted arm.

7. A machine as claimed in claim 2, in which the pivoted arm includes means cooperating with the key for stopping rotation of the shaft when said pivoted arm is engaged by the slidable key.

8. In a safety mechanism for disengaging a coupling between a shaft and the driving member of a machine including a coupling member slidable parallel to the shaft, means for biasing the coupling member to coupling position and a wedge-shaped member movable into the path of the coupling member for engaging and moving it out of its coupling position, the improvement comprising means for biasing said wedge-shaped member away from the path of the coupling member, means operable on rotation of the shaft for rocking said wedge-shaped member into the path of said coupling member without normally occurrence of a fault in the operation of the machine for retaining the wedge-shaped member in its rocked position in the path of said coupling member, whereby the wedge-shaped member is engaged by the coupling member and the latter being interconnected with said wedge-shaped member and arranged to be pulled when said wedge-shaped member is rocked to its uncoupling position, a rocker shaft to which the other end coupling member is in its engagement position with respect to the wedge-shaped member.

JOHANNES HUBERTUS VAN HAANDEL,

Legal representative of the heirs and of the estate of Adrianus van Haandel, deceased.

References Cited in the file of this patent UNITED STATES PATENTS 

